Speckle field decorrelation nature in holographic interferometry with spatially modulated reference wave

The influence of reference wave spatial modulation on visibility of the interference fringes in holographic interferometry of diffusely scattering objects is considered. It is shown that the presence of the points with null intensity in the speckle fields causes the distortion of micro- structure of the reconstructed speckle fields even using a reconstructing wave identical to the reference one. As a result, the interfering fields became partially decorrelated and this leads to the noticeable decrease of the holographic interferograms visibility.